InRainbows, I am pleased to report that I have an answer to your question and it's all good. I was worried that I might have missed the boat and my uncle in Australia might be pushing up the daisies by now (he is 83) but apparently not, he is still alive and well and working on the latest edition of his law textbook. The "estrangement" story (according to my uncle) was all nonsense; he applied for a PhD scholarship at the Australian National University, went over there, he was subsequently offered a full time job at the university, got married, and the rest as they say is history. So the lesson from that is: don't believe anything about estrangement until you have heard both sides of the story.
Also, I now have an extended family in Australia in the form of two cousins and their children and partners. The Aussies seem a cheery lot and TBH I feel more like hanging out with them than with my own miserable, ungrateful, narcissistic kids, unless the latter go and get themselves personality transplants.
We will try to stay in touch from now on. All (well, mostly) thanks to GransNet.